Pipe line construction method

ABSTRACT

A method of construction an insulated pipe line and vehicular supporting means across an unstable surface including the steps of driving or otherwise inserting piling into the supporting surface along the pipe line path, pre-forming elongated hollow pipe-supporting structures having an upper surface capable of supporting vehicles, setting the structures on the piling by means of a crane which travels along the top of the structures already placed in position, eliminating the possibility of inadequate support, and then placing the pipe within the structure, again from the top of the structure, and sealing the structure from the outside atmosphere, simultaneously forming a relatively flat surface for vehicular traffic.

United States Patent Hopkins [4 1 Dec. 19, 1972 [541 PIPE LINE CONSTRUCTION METHOD [72] Inventor: John P. Hopkins, Mercer Island,

1 Wash.

[73] Assignee: John P. Hopkins Co., Mercer Island,

Wash.

[22] Filed: Aug.vl0, 1970 [21] Appl. No.: 62,372

[52] US. Cl. ..29/428, 14]], 14/75,

14/77, 92/1, 61/721, 61/725 [51] Int. Cl. ..B23p 19/00 v [58] Field of Search ..29/428, 455; 14/1, 3, 4 X,

14/14, 75 X, 77 X; 92/1, 22; 61/721 X, 72.3, 72.4, 41 A, 41 R725 [56] References Cited UNITED STATES PATENTS 2,855,617 10/1958 Broms ..l4/l3 3,208,086 9/1965 Gillois ..l4/1 3,208,087 9/1965 Edwards.. ....l4/l3 3,490,605 l/197O Koss ..l4/1 3,571,835 3/1971 Buechler ..l4/l 3,292,379 12/1966 McElvany ..6l/72.5

FOREIGN PATENTS OR APPLICATIONS 778,352 12/1934 France ..l4/75 Primary Examiner.lohn F. Campbell Assistant Examiner-Donald P. Rooney Attorney-Seed, Berry & vDowrey [57] ABSTRACT A method of construction an insulated pipe line and vehicular supporting means across an unstable surface including the steps of driving or otherwise inserting piling into the supporting surface along the pipe line path, pre-forming elongated hollow pipe-supporting structures having an upper surface capable of supporting vehicles, setting the structures on the piling by' means of a crane which travels along the top of the structures already placed in position, eliminating the possibility of inadequate support, and then placing the pipe within the structure, again from the top of the structure, and sealing the structure from theoutside atmosphere, simultaneously forming a relatively flat surface for vehicular traffic.

9 Claims, 8 Drawing Figures PATENTED B 19 I97? 3.706.125

' SHEET 1 [IF 3 INVEN JOHN P. HOPKI ATTORNEYS PATENTEDBEB 19 I972 SHEET 2 or 3 1 INVENT JOHN P. HOP S ATTOR NEYS PATENTEDIIEB19 m2 3; 706; 125

SHEET 3 [IF 3 INVENTOR. JOHN P. HOPKINS ATTORNEYS PIPE LINE CONSTRUCTION METHOD BACKGROUND OF THE INVENTION The discovery of oil supplies on the Alaskan North Slope have presented a myriad of novel problems with respect to extricating and transporting the oil to places of large demand or to locations of economical refinement. With respect to the transportation of the oil, one of the problems which must be solved is how to transport the oil which leaves the ground at a temperature of about 175 F. across the frozen tundra without critically changing the environment. Close proximity of this temperature to the ground results in a defrosting of the tundra which would cause the oil-carrying pipe structures to sink beneath the surface, causing leakage or breakage. Likewise, cooling of the oil decreases its fluidity and impedes the transportation thereof.

It has been proposed to dig a trench approximately to 12 feet deep and 10 to 12 feet across and lay the pipe within the trench surrounded by approximately 5 feet of gravel, thus insulating the pipe and its contents from the frozen ground. This method of insulating the pipe has proven to be unsatisfactory in that with the unevenness of the terrain, many times the pipe will become too close to the ground and thaw the tundra causing, as noted above, an instability in the supporting ground and a sinking or perhaps breakage of the pipe. An additional problem of this type of construction is the lack of ability to visually inspect the pipe for breaks or leaks. Damage of this sort may go undetected for some time causing a loss of the valuable material being transported and further, a pollution of the surrounding area.

Conventional pipe-laying methods require the construction and maintenance of roads both during the actual construction of the pipe line and later for inspection and maintenance of the line. The need for an additional road over unstable terrain is unduly burdensome and particularly where the surface is subjected, as is the Alaskan North Slope, to periodic thawing and freezing.

With the above-noted problems in mind, it is proposed that the pipe line used for transporting the crude oil from a well across the tundra to a point of refinery or loading onto conventional transportation means be done in a structure which is located a substantial distance above the tundra, insulating the tundra from the heat of the oil by an air gap. Further to insulate the structure, it is proposed that the pipe be enclosed within a sealed structure providing additional insulation for the material being transported from the extremely cold surrounding atmosphere. It is contemplated that the structure which encloses the main pipe could likewise well be large enough to support additional oil-carrying capacity, thus greatly decreasing the relative cost of the structure.

It is therefore an object of the present invention to construct a pipe line particularly for use on the Alaskan North Slope, but not limited thereto, in a method which will not greatly damage the tundra during the construction and, secondly, will sufficiently insulate the hightemperature transmittal pipe from both the atmosphere and the supporting tundra.

It is another object of the present invention to construct a pipe line by a method which minimizes the amount of time the tundra need be directly used to support construction apparatus, eliminating the need for a parallel road.

Yet another object of the present invention is to construct a pipe line by a method which enables fabrication over unstable ground while greatly eliminating the danger of material damage to the environment. I

Still a further object of the present invention is to construct a pipe line in such a fashion that its upper surface is capable of use for vehicular traffic.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view of one method of securing the pipe line supporting piling in position;

FIG. 2 is a perspective view showing the pipe-supporting structure being positioned inv place and the required equipment for performing the operation;

FIG. 3 is a perspective view of the pipe-laying equipment traversing the top of the pipe-supporting structure and laying the pipe within the structure;

FIG. 4 is a perspective of the structure being sealed;

FIG. 5 is a front elevational view through the pipesupporting structure indicating a possible location for supporting the wheels of the pipe-laying mechanism;

FIG. 6 is a front elevational view of the pipe-supporting structure with the sealing top member in place and the pipe in position;

FIG. 7 is a transverse elevational view through the pipe-supporting structure with the pipe in position;

FIG. 8 is a front elevational view of a modified form of the pipe-supporting structure including two extensions for supporting two additional pipe lines.

DETAILED DESCRIPTION OF THE DRAWINGS As can be seen consecutively in FIGS. 1-4, the sequence of operations in laying the pipe line over unstable terrain such as frozen tundra is generally as follows: First, as depicted in FIG. 1, the equipment-supporting piling 2 must be placed in position. This operation can be done either as depicted by drilling holes within the frozen surface and inserting the piling by a crane 4 or alternatively by driving the piling into the surface. Once a plurality of piling is in position, a spanning cap structure 6 is placed upon the top to give uniform support to the structure placed thereon. Another method of inserting the pilings within the scope of the present invention and one which may be necessary during a warm spell where the upper surface of the tundra has softened, would be to use a boom mounted upon the structure, already secured in place, to insert a set of pilings for the next section. This particular method has not been illustrated in that it would use no more than the equipment shown with respect to other method steps and is believed to be well within the scope of one skilled in the art.

As seen in FIG. 2, once the pilings 2 are in position and the cap 6 placed thereupon, a hollow structural pipe-supporting member 8, hereinafter specifically described, is placed in position spanning the sets of pilings.

It is contemplated that the structural members, as well as the pipes to be hereinafter described with regard to placement thereof, be manufactured at several locations placed conveniently along the path of the pipe line. The section 8 then would be placed upon the top of a presecured structural member 8 and rolled into position adjacent the last laid section whereat the new section would be picked up by a heavy-duty crane 12 having a base 14 which would span the open section of the pipe-supporting structure 8 and guided by outriggers l6. Mounted upon the base 6 and 14 would be a heavy-duty turntable l8 and associated boom structure 20 of such strength to enable it to pick up an entire new section, pivot about the central point of the base structure through 180 and place the new section in position as shown in dotted lines in the figure.

Once a number of the pipe-supporting structures 8 are secured in place, a length of welded pipe sections 22 would be wheeled into position using either a single or plurality of A-frame type structures 24 having appropriate wheels andv guiding members 26. When the pipe is in the proper position for abutting the previously laid pipe section, it will be lowered onto supports 28, more specifically described hereinafter, and welded into position. A I

As shown in FIG. 4, the same A-frame type structure as used for laying the pipes could likewise well beused for laying the sealing or capping member upon the pipe-supporting sections. The cap member 31 would likewise, as hereinabove described, be wheeled into position by an A-frame member and lowered into position abutting the previously laid cap, thus forming a completely sealed pipe-supporting structure which is insulated from the outside atmosphere and yet allows ready accessibility for pipe repair and/or inspection. It is to be emphasized at this point that the upper surface of the pipe line, when completed, is of sufficient strength to support vehicular traffic. The term vehicular traffic is intended to incorporate traffic including automobile, train or any other ground-supported vehicle.

Referring now to FIGS. 5, 6 and 7, in combination, it can be seen that the pipe-supporting structure 8 comprises a base section 30, a pair of parallel uprights 32 having located upon the inner side thereof reinforcing elements 34. The upper surface of the side portions 32 is substantially T-shaped, having horizontal members 36 which have a ledge element 38 upon the interior edge thereof for supporting a cap, hereinafter described. The T-shaped structure 36 serves to support both the successive structural-laying device 14 which, as noted above, has weight-supporting wheels and outriggers 16. As pointed out above, the Outriggers wheels 16 serve to guide the apparatus 14 along the previously-laid structural sections 8. The entire section 8 is supported on a plurality of pilings 2 and a cap element 6. As seen in FIG. 6, the pipe section 22 has now been placed within the structural support section and the cap 28 placed in position, enclosing the pipe. It is to be noted at this point that the pipe-supporting element 28 is of any desirable configuration, but should be designed such that the pipe will not roll transverse to its axis, but yet be placed upon some sort of a movable element such as wheels 29, enabling it to expand and contract along its axis as required by temperature variations.

ln FIG. 7, the structural support element can be seen as well as a section of pipe 22 in position. It is to be noted that the ends of the structural support sections 8 abut approximately centralized upon the cap member 6 on top of the pilings 2. To assure a substantially airtight seal, there is provided a gasket member 40 around the entire abutting edge of the structural support members.

Since it is within the contemplation of the invention that the structure would not be used for a strictly a single pipe line, there is depicted a structural member in FIG. 8 which is functionally the same as that hereinabove describedwith a structural modification in that it would need a larger cap member 6 placed on a greater number of pilings 2. The structural support member 8 has also been modified by the addition of extensions 42 which are sufficiently wide to support additional pipe lines. It is, of course, within the contemplation of the present invention to insulate these exterior pipe lines as they would not Shave a fully-enclosing structural member surrounding them. It is to be noted at this point that, even though the outlying pipe lines do not have a completely surrounding structure, the fact that they are insulated does not deter from inspection for leakage or breakage. The additional lines would be within a channel-type member and any leaks or breakage would be apparent from the existence of fluid within the channel members.

Thus, the method, hereinabove described, allows the construction of the pipe line with a minimum of disturbance to the supporting earth surface, effectively insulates the surface from temperature differences of the fluid transported within the pipe and further provides a supporting surface or roadbed for maintenance equipment and/or general vehicular traffic.

The embodiments of the invention in which an exclusive property or privilege is claimed are defined as follows:

1. A method of laying a pipe line across a surface such as tundra subject to loss of stability comprising;

inserting piling far enough into the surface to provide stable support along the pipe line even though the upper surface of the tundra has thawed, constructing a pre-formed hollow elongated structural unit on top of the piling by the steps of prefabricating aplurality of hollowidentical sections, placing a first section in position spanning the distance between spaced sequential sets of piling, using the first section as a support for the equipment necessary to lay the next section as well as a support for the following sections which will be transported and stored on previously placed sections prior to placing the sections in endabutting relationship upon the pilings, and repeating the procedure until the units span the entire length of the pipe line, and

mounting a fluid transporting pipe within the structural unit spaced from the walls of the section whereby the pipe is insulated from the surrounding atmosphere and supported upon a stable surface unaffected by the temperature of the material transported within the pipe.

2. A method as in claim 1 wherein the hollow structural unit is positioned having an open top and the pipe is transported in sections by a vehicle supported by the upwardly facing edges of positioned sections .to positions and lowered through the top of the contiguous sections into end-abutting relationship with the previously placed pipe sections.

3. A method as in claim 2'and further including the step of transporting and securing a cover member upon the unit.

4. A method as in claim 1 and further including the step of pre-drilling the holes for the piling and inserting said piling from a ground-supported vehicle.

5. A method as in claim 1 and further including the step of inserting the piling from apparatus supported upon a section of the hollow structural unit.

6. A method as in claim 1 and further including the step of placing insulated pipe upon extensions provided on the structural unit.

7. A method of constructing an insulated pipe line and vehicular supporting surface comprising;

driving a plurality of sets of piling into the supporting surface, extending above the surface and having a predetermined distance between the sets,

forming elongated hollow structures having sufficient length to span the distance between the sets of piling,

placing and securing at least one section of the elongated structure upon the piling and spanning the LII distance therebetween,

mounting a mobile crane upon the top of the elongated structure mounted in position,

moving the crane along the top of the structure and sequentially placing further structures in endabutting relationship along the line,

placing a transmission pipe by insertion from top within the structure at a position spaced from the walls of the structure, and

sealing the structure whereby the material within the pipe may be transported at a temperature diverse from the temperature of the environment.

8. A method as in claim 7 wherein the pipe is moved along the top of the secured structures in sections and lowered into the structures to be welded in place.

9. A method as in claim 7 wherein the sealing step includes placing a cap upon the top of the structure of sufficient strength to support vehicular traffic. 

1. A method of laying a pipe line across a surface such as tundra subject to loss of stability comprising; inserting piling far enough into the surface to provide stable support along the pipe line even though the upper surface of the tundra has thawed, constructing a pre-formed hollow elongated structural unit on top of the piling by the steps of prefabricating a plurality of hollow identical sections, placing a first section in position spanning the distance between spaced sequential sets of piling, using the first section as a support for the equipment necessary to lay the next section as well as a support for the following sections which will be transported and stored on previously placed sections prior to placing the sections in end-abutting relationship upon the pilings, and repeating the procedure until the units span the entire length of the pipe line, and mounting a fluid transporting pipe within the structural unit spaced from the walls of the section whereby the pipe is insulated from the surrounding atmosphere and supported upon a stable surface unaffected by the temperature of the material transported within the pipe.
 2. A method as in claim 1 wherein the hollow structural unit is positioned having an open top and the pipe is transported in sections by a vehicle supported by the upwardly facing edges of positioned sections to positions and lowered through the top of the contiguous sections into end-abutting relationship with the previously placed pipe sections.
 3. A method as in claim 2 and further including the step of transporting and securing a cover member upon the unit.
 4. A method as in claim 1 and further including the step of pre-drilling the holes for the piling and inserting said piling from a ground-supported vehicle.
 5. A method as in claim 1 and further including the step of inserting the piling from apparatus supported upon a section of the hollow structural unit.
 6. A method as in claim 1 and further including the step of placing insulated pipe upon extensions provided on the structural unit.
 7. A method of constructing an insulated pipe line and vehicular supporting surface comprising; driving a plurality of sets of piling into the supporting surface, extending above the surface and having a predetermined distance between the sets, forming elongated hollow structures having sufficient length to span the distance between the sets of piling, placing and securing at least one section of the elongated structure upon the piling and spanning the distance therebetween, mounting a mobile crane upon the top of the elongated structure mounted in position, moving the crane along the top of the structure and sequentially placing further structures in end-abutting relationship along the line, placing a transmission pipe by insertion from top within the structure at a position spaced from the walls of the structure, and sealing the structure whereby the material within the pipe may be transported at a temperature diverse from the temperature of the environment.
 8. A method as in claim 7 wherein the pipe is moved along the top of the secured structures in sections and lowered into the structures to be welded in place.
 9. A method as in claim 7 wherein the sealing step includes placing a cap upon the top of the structure of sufficient strength to support vehicular traffic. 